Sterilizer



Dec. 3935. R JEWELL ET AL 2,024,004

STERILIZER Filed om. 24, 1932 ATTORNEYS.

Patented Dec. 10, 1935 UNITED STATES PATENT OFFICE STERILIZERv Application October 24, 1932, Serial No. 639,316

Claims.

Sterilizers of some types are charged with steam for sterilizing fluid and the eiectiveness of the sterilizing depends greatly upon the clearing of the sterilizing chamber of its original air content. In order to accomplish this it is desirable to use a thermostatically responsive valve which will permit the discharge of air and condensate, but which will close as soon as the steam, or heated gas, reaches it. In such discharge foreign matter may be carried into the discharge and interfere with the proper operation of the thermostatic valve. The present invention is designed to obviate this difficulty. In the operation of such sterilizers it is also common to clear them with an ejector putting the sterilizer'under subatmospheric pressure. Where this is done and there has been supplied a device for discharging the original air from the sterilizer chamber there is a tendency to indraw air through the discharge passage when the ejector is operating. It is desirable to prevent this indrawing so as to prevent the reverse movement of any material that may be passed into the discharge passage. It is desirable to have the discharge passage lead from the lowest, or approximately the lowest point of the sterilizer so that any accumulation of condensation will pass out through the discharge passage. This with the fact that it may carry with it obstructing material increases the danger as to a complete stoppage of the discharge and in order to obviate this possibility an auxiliary discharge is preferably provided leading from a higher elevation in the sterilizer chamber so as to be out of the range of the accumulated condensate, under which conditions this elevated discharge carrying, therefore, only air and steam is less likely to be obstructed and thus the assurance of the displacement of al1 the original air is made more certain.

A preferred embodiment of the invention is illustrated in the accompanying drawing as follows:-

Fig. 1 shows an elevation of a sterilizer, parts being broken away in section to better show construction.

Fig. 2 shows a similar view showing a modication.

Fig. 3 is a section on the line 3-3 in Fig. 2.

I marks the sterilizer chamber. Steam is delivered to the chamber through a valve 2 which is adapted to deliver steam to the chamber and to an ejector 3 for evacuating the chamber. The sterilizer is provided with a discharge 4 leading to an inlet 4a of a chamber 5 in a fitting 6. A screen 'I separates the chamber 5 from the outlet chamber 8. The chamber 8 discharges through a valve opening 9 which is controlled by a non-return check valve I0, the check valve being provided with a cage II. The tting has a discharge opening I2 and a pipe I2a leads from 5 this opening to a thermally actuated valve I3. A discharge I4 leads from this valve usually to some vented drain, or vented sewer connection. The thermostatic valve is of the ordinary type having a seat I5, a valve head I3, and a ther- 10 mally sensitive bellows I'I. The bellows is yieldingly mounted through a clip I8 with a cap I9 of the valve. Under ordinary temperatures the bellows maintains the valve open, but as soon as it is subjected to heat from discharging steam l5 it closes the valve through the expansion of the bellows. A cap 29 is provided for the tting 6 and this is removably attached to the fitting by screws 2|. The cap is provided with a flanged opening 22 which is closed by a transparent cover 20 23. The transparent cover is held in place by a ring 24 which is screwed into the cap against the transparent cover. The ttng is preferably tilted and placed in such position as to be readily observed by the operator of the sterilizer and the 25 attendant can observe the accumulation of material on the screen through this transparent cover.

A similar flanged opening 25 is provided over the check valve and this is closed by a transparent cover 26, the cover 26 being secured in the cap by a ring 21 which is screwed into the opening against the cap. This permits the operator, or attendant, to observe the action of the check valve and thus be assured of its operative condition.

In the modied structure the sterilizer is provided with a discharge 28 which leads from approximately the bottom of the sterilizer and thus carries with it all the condensate. This leads to a tting 29 provided with a strainer 30, the details of the strainer structure being similar to that of the iitting 6 except that it is not supplied with a check valve. A pipe 3l leads from the tting 29 and this leads to the inlet of a tting 45 32 identical in structure with the tting 6 including the strainer and check valve. A pipe 33 leads from the discharge of the fitting 32 to a thermally actuated valve 34 which is identical in structure with the valve I3. An auxiliary discharge 35 50 leads from the sterilizer receptacle at a higher level than the discharge 28 and it is, therefore, out of the range of any accumulation or condensate and simply discharges air and being off the bottom is less apt to receive obstructing material.

The discharge conduit A35 leads to the conduit 3l In this way an assured outlet passage for the displacement of air as the sterilizer is charged with steam is more certainly assured and consequently a complete sterilization more certainly assured.

It will be noted that the check valve operates as an indicator indicating to the operator the passage of air as it is discharged from the receptacle. Usually also there is some accumulation of condensate, or lodgment of material on the strainer, the disturbance of which is visible through the cover 23 and thus visually indicates to the operator a discharge movement of air from the sterilizer. Y Y Y What We claim as new is:-

1. In a sterilizer, the combination of a sterilizer receptacle; a thermally controlled exhaust valve; and fluid discharge conduits leading from the receptacle to the exhaust valve, one of said conduits leading from the bottom of the receptacle and the other of said conduits leading from a higher level in the receptacle.

2. In a sterilizer, the combination of a sterilizer receptacle; a thermally controlled exhaust valve;

fluid discharge conduits leading from the receptacle to the exhaust valve, one of said conduits leading from the bottom of the receptacle and the other of said conduits leading from a higher level in the receptacle; and a strainer for both conduits in advance of the thermally controlled exhaust valve. Y

3. In a sterilizer, the combination of a sterilizer receptacle; a thermally controlled exhaust valve; fluid discharge conduits leading from the receptacle to the exhaust valve, one of said conduits leading from the bottom of the receptacle and 5 the other of said conduits leading from a higher level in the receptacle; and a. check valve preventing a back-now through said conduits.

4. In a sterilizer, the combination of a sterilizer receptacle; a thennallycontrolled exhaust valve; l0 fluid discharge conduits leading from the receptacle to the exhaust valve, one of said conduits leading from the bottom of the receptacle and the other of said conduits leading from a higher level in the receptacle; a strainer for both con- 15 duits in advance of the thermally controlled exhaust valve; and a check valve preventing a return flow through said conduits.

5. In a sterilizer, the combination of a sterilizer receptacle; a thermally controlled exhaust valve; 20 fluid discharge conduits leading from the receptacle to the exhaust valve, one of said conduits leading from the bottom of the receptacle and the other of said conduits leading from a higher level in the receptacle; a strainer in the low level conduit; and a strainer and check valve through which the Huid from both conduits pass to the thermally controlled valve.

RAYMoND L. JEWELL. 30 WEEDEN B. UNDERWOOD. 

